Supply Demand Research Articles

Valorization of Biomass Through Anaerobic Digestion and Hydrothermal Carbonization: Integrated Process Flowsheet and Supply Chain Network Optimization

Utilization of biomass through anaerobic digestion and hydrothermal carbonization is crucial to maximize resource efficiency. At the same time, supply chain integration ensures sustainable feedstock management and minimizes environmental and logistical impacts, enabling a holistic approach to a circular bioeconomy. This study presents an integrated approach to simultaneously optimize the biomass supply chain network and process flowsheet, which includes anaerobic digestion, cogeneration, and hydrothermal carbonization. A three-layer supply chain network superstructure was hence developed to integrate the optimization of process variables with supply chain features such as transportation modes, feedstock supply, plant location, and demand location. A mixed-integer nonlinear programming model aimed at maximizing the economic performance of the system was formulated and applied to a case study of selected regions in Slovenia. The results show a great potential for the utilization of organic biomass with an annual after tax profit of 23.13 million USD per year, with the production of 245.70 GWh/yr of electricity, 298.83 GWh/yr of heat, and 185.08 kt/yr of hydrochar. The optimal configuration of the supply chain network, including the selection of supply zones, plant locations and demand locations, transportation links, and mode of transportation is presented, along with the optimal process variables within the plant.

Resilience assessment of water supply and demand in the Yellow River Basin based on integrated optimisation weighting–improved grey-target model

Context As a result of the combined impacts of global climate change and intensive human activities, the water-resources supply–demand imbalance has become prominent, particularly in the Yellow River Basin. Aims This study aims to accurately assess the changes in resilience of water-resource supply and demand over the past few decades. Methods This study examines the resources, economy, society, and ecology of both the supply and demand aspects in assessing the resilience of water supply and demand. The composite evaluation model based on integrated optimisation weighting and an improved grey-target model was constructed. Key results Using the Yellow River Basin as an example, from 2011 to 2020, the resilience index of the water-resource supply–demand system (RIWRSS) in the Yellow River Basin increased significantly by 69.4%. Among the 12 indicators in the Yellow River Basin, the contribution proportion of the inhibiting factors decreased by 3.7%, whereas the contribution of the driving factors increased by 70.9%. Conclusions The present study has provided insights into evaluating the RIWRSS and highlighted resilience disparities between the supply and demand sides in the Yellow River Basin. Implications This study expects to provide evidence for the improvement of water-supply conditions of water resources in the Yellow River Basin.

Exploring the Transmission Process of Carbon Sequestration Services and Its Applications: A Case Study of Hainan

The pressing need to address climate change and advance global sustainable development has heightened the emphasis on ecosystem services, especially carbon sequestration. This research assesses the supply and demand dynamics of carbon sequestration services on Hainan Island, China, highlighting its significant contributions to global biodiversity conservation and carbon balance. The analysis considers the spatial distribution and interrelation of these services in light of recent land use and ecological policy changes. The methodology incorporates land use and land cover data, the Normalized Difference Vegetation Index (NDVI), meteorological data, and soil data. A gravity model is employed to elucidate the supply–demand relationship for carbon sequestration services, examining the flow across different regions and identifying spatial connections and their intensities. The results indicate a notable increase in carbon sequestration supply in Hainan from 2000 to 2020, particularly in the central mountainous areas. Conversely, the demand for these services has risen, especially in the northern plains’ urban areas and southern coastal towns. The gravity model reveals a strong spatial interdependence between the central mountainous supply zones and the high-demand urban locales. This study underscores the disparities in carbon sequestration supply and demand on Hainan, emphasizing the need for the strategic management of these elements. It provides critical data for ecological compensation policies and offers insights into the roles of regional ecosystems in climate change mitigation. The research highlights the necessity of incorporating ecosystem services into land-use planning and decision-making to foster sustainable development and strengthen climate resilience.

Older people’s social work safe staffing supply and workforce demands analysis: A case study from Northern Ireland

Abstract In the UK, a range of operational tools and policy guidelines regulate staffing in various Health and Social Care sectors. Nonetheless, frameworks to ensure safe staffing in social work remain less advanced. This study focuses on older people’s social work community teams in Northern Ireland due to the high volume of cases and vacancies within these teams. Our findings provide evidence based on actual caseloads (direct work with service users) and workloads at individual, team, and regional levels within this programme of care. The analysis revealed systemic issues that require systemic solutions in relation to staffing supply and service demands. Frontline social workers and managers frequently faced overwhelming worker-to-caseload ratios, routine use of waiting lists, and team vacancies. These findings lay the groundwork for evidence-based strategic planning, guiding the development and enactment of safer and more effective social work policies and legislation in the years ahead. The project was commissioned by the Department of Health, Northern Ireland in preparation for policy and legislative developments expected between 2025 and 2028.

Financial Barriers to Expanded Birth Center Access in New Jersey: A Qualitative Thematic Analysis.

Birth centers are an underused care setting with potential to improve birth experience and satisfaction. Both hospital-based and freestanding birth centers operate with the midwifery model of care that focuses on safe, low-intervention physiologic birth experiences for healthy, low-risk pregnant people. However, financial barriers limit freestanding birth center sustainability and accessibility in New Jersey, especially for traditionally marginalized populations. This qualitative study explores the financial barriers faced by freestanding birth centers in order to expand access and choice for pregnant people in New Jersey. Semistructured interviews were conducted with participants from 4 sectors: (1) birth center or health system, (2) policy-adjacent philanthropy or research, (3) state departments, and (4) health insurance. Coding and analysis followed a reflexive thematic analysis process, resulting in the identification of 4 financial barriers to birth center access. Facility Medicaid reimbursement rates are a primary barrier for birth centers, along with startup and operating costs and, more indirectly, low supply of midwives and low patient demand for birth center care. New Jersey is well-positioned to enact critical policies and programs that can improve out-of-hospital birth center access, based on the findings and recommendations from this research. Other states can follow suit in pursuit of solutions to improve maternal health access and equitable birth center sustainability.

Bulk System Reliability Assessment Incorporating Nodal Correlations in Supply–Demand Variabilities and Uncertainties Created with Net-Zero Emission Targets

Bulk System Reliability Assessment Incorporating Nodal Correlations in Supply–Demand Variabilities and Uncertainties Created with Net-Zero Emission Targets

Dynamic coupling of qualitative–quantitative models for operation of water resources based on environmental criteria

Concerning issues include the distribution of scarce water resources, the quality of utilized water, environmental repercussions, and regulations for the sustainable use of water resources. In the management of water resources, optimal qualitative–quantitative exploitation of surface water bodies is regarded as a desirable strategy. The Dez River surface water system from the Dez regulatory dam to Band-e-Ghir is selected in the current paper to create a qualitative–quantitative model that can determine the best exploitation strategies. A dynamic linkage between qualitative and quantitative models is built in order to simulate the current exploitation conditions under the umbrella of the best-case scenario. In this coupled system, hydraulic relationships are established between all of the system’s components. The available data are shared between two models in this structure to simulate the qualitative and quantitative effects of surface water. Then, a new structure is produced to derive the best policies for exploiting the dam and the river by connecting the multi-objective particle swarm optimization algorithm with the qualitative–quantitative coupled model body. The monthly river environmental demand is one of the decision variables in the ideal scenario, and the goals include boosting the percentage of supply demands and minimizing the violation of quality standards. The best-case scenario’s implementation increases the likelihood that all plain demands will be met, regardless of priority. Furthermore, in comparison with the reference scenario, the results of the optimal scenario show that not only are the concentrations of contaminants and qualitative parameters increased, but there are also only minimal violations of the quality and pollution standards of the river water in the majority of river points, particularly in the locations of agricultural withdrawals. The findings demonstrate that using the qualitative–quantitative dynamic relationship between water resources and the development of the coupled model using the NSGA-II algorithm allows us to better plan for the appropriate use of existing water resources by taking into account all stakeholders in such a way that, in addition to meeting needs, maintains the river quality close to standard limits throughout the exploitation period. By using this strategy, users will be informed of the negative effects of their actions, as well as the encroachment on river boundaries and associated consequences.

Dynamic Trends in Aquatic Product Supply and Consumption in China: Implications for Sustainable Diets and Environmental Impact Reduction

Aquatic foods play a pivotal role in transforming food systems. As the world’s leading producer, consumer, and trader of aquatic products, China’s potential for sustainable supply and consumption is critical to understand. The aim of this study was to depict the dynamic trends of aquatic products and the consequences of sustainable diets and environmental impacts. A panel dataset about Chinese aquatic products covering the period from 1952 to 2023 was drawn for analysis. Diet sustainability was assessed with the deviation from the Dietary Guidelines for Chinese Residents (2022) and EAT-Lancet recommendations. The environmental impacts of aquatic products’ supply and consumption were assessed using carbon footprints and water footprints. The findings reveal that aquatic products’ supply increased from 4.65 million tons to 71.16 million tons from 1978 to 2023, and annual aquatic food consumption per capita increased from 3.50 kg in 1978 to 15.20 kg. While overall supply meets consumption needs, structural imbalances persist at the provincial level. Over time, the influence of marine fishery products has declined from 1.06 million tons (63.63%) in 1952 to 35.85 million tons (50.38%) in 2023, whereas offshore aquaculture shows promising potential for meeting future supply demands (23.96 million tons in 2023, accounting for 66.82% of marine fishery production). To align with healthy dietary goals and environmentally sustainable food systems, provincial aquatic food demand across China was adjusted. The carbon footprints and water footprints of both current and adjusted consumption patterns were also assessed. The results indicate that adjusting consumption based on the Dietary Guidelines for Chinese Residents (2022) and EAT-Lancet recommendations could reduce environmental impacts to different degrees. The findings could offer valuable references and insights into developing sustainable strategies in aquatic product management and advancing food system transformation.

Assessing Customer Satisfaction with Privatized Electricity Service Quality in Nigeria

The privatisation of electricity service delivery in Nigeria was more than ten years ago. The privatisation policy was in an attempt to ensure a stable electricity supply to the end users. The outcome of the power privation is being appraised by the paper via evaluation of the customer‟s satisfaction as one of the measuring factors of its performance. It is objectively an appraisal of the perception of the electricity service delivery and users as outcome of the privatisation of power supply. Relevant literature was sourced as secondary data and a conceptual framework that depicts indices of customer satisfaction was explored to substantiate the satisfactory level of the customer, the end user of electricity service delivery. An inventory of the outcome of electricity privatisation was also embarked on, sourcing information about the customers‟ satisfaction with the service quality of electricity service delivery privatisation from available relevant publications and social media. The paper in its empirical study looked at 397 sample size customers‟ satisfactory response to electricity service deliveryin Ekiti State as a case study. Considered their perception from the inception of the electricity privatisation policy in the past 10 years, from November 2013 to date in 2024. The paper, therefore, concluded in its submission, having garnered from the available information of the negative response of the customers perceptions. This is a reflection of the poor performance of power privatisationbefore and after the power privatization policy. The paper, given the foregoing, recommends the consideration of the dynamics in demography,spatial distribution and demand of power supply in the privatization process in Nigeria.

Red Blood Cell Transfusion - Indications, Informed Consent and Associated Risks

The aim of red blood cell (RBC) transfusion is to prevent or treat anemic tissue hypoxia in acute or chronic anemia. In 2022, approximately 3.2 million red blood cell transfusions were conducted in Germany. Most blood products are transfused in surgical medicine. RBC units should be used appropriately, based on recent evidence about their indications, profound knowledge on handling, correct documentation as well as possible associated risks of transfusion-associated adverse events and their respective treatments. Blood loss in particular increases the risk of an imbalance between oxygen supply and oxygen demand. Targeted, rational (restrictive) blood transfusion based on physiological transfusion triggers makes it possible to avoid organ injury due to anemic hypoxia.

Efficient Neutrosophic Optimization for Minimum Cost Flow Problems

In the domain of optimization, linear programming (LP) is recognized as an exceptionally effective method for ensuring the most favorable outcomes. Within the context of LP, the minimum cost flow (MCF) problem is fundamental, with its primary objective being to reduce the transportation costs for a single item moving through a network, under the constraints related to capacity. This network is made up of supply nodes, directed arcs, and demand nodes and each arc has an associated cost and capacity constraint, these factors are certain. However, in practical scenarios, these factors are susceptible to variation due to causal uncertainty. The neutrosophic set theory has surfaced as a challenging approach to tackle the uncertainty that is often encountered in optimization processes. In this manuscript, our primary objective is to address the minimal cost flow (MCF) problem while accounting for the uncertainty inherent in the neutrosophic set. We specifically focus on the cost aspect as SVTN numbers and introduce a new approach based on a customized ranking function handmade for the MCF problem a pioneering endeavor within the field of neutrosophic sets. Additionally, we present numerical example to validate the effectiveness and robustness of our model.

STUDY OF COPPER ELECTRO PLATING ELECTROLYSIS PROCESS ON MILD STEEL MATERIAL

Copper plating or copper electroplating is a massive industry that is rising enormously across the globe. It is considered a highly refined and effective method in the metal coating industry. However, copper in itself is very expensive because of the limited supply and high demand. The reason the demand for copper is high is that it is a vital component used for everything from plumbing, wiring, electronics to industrial fertilizers and pesticides. Copper is considered a miracle metal because of its unique properties this metal is malleable, it conducts electricity, resists corrosion and the best part is it can easily take on a variety of shapes

Investigation of Menounat coal beneficiation – Bechar deposit, for super clean concentrate recovery

ABSTRACT Although Algeria’s coal reserves are 246 Tg, no coal field is operational since 1970, and almost all our energy sources are gas and oil. Regarding the strong demand for an affordable coke supply of the Algerian steel industry compounded by the many other social economic motives, the present study investigates, for the first time, the beneficiation of the Algerian coal in Menounat seam (Bechar, Abadla basin). Different characterization methods, for instance, petrographic, mineralogic, and thermal, were carried out to define significant constituents that may have influence on coal processing. Washability was analyzed by sink-floats tests that show negative results for physical cleaning applicability, whereas floatability was examined by release tests. Ultimate, proximate, and petrographic analyses confirm the rank that is high volatile bituminous coal with appreciable properties corresponding to low ash content less than 10%, around 3% of moisture, and high heating value above 6900 kcal/kg, while having high sulfur content of nearly 2% was the main environmental concern. Regardless of negative washability data obtained, froth flotation using fresh prepared emulsified diesel oil shows interesting result of a super clean concentrate with lower ash content down to 3% and sulfur content less than 1.3%.

Predicting age at first calving of dairy breed calves using whale optimization-based ensemble learning framework

Dairy product requirement and the demand–supply gap of milk in Ethiopia have been increasing at an alarming rate due to various factors such as shortage of animal’s feeds, feed staffs, feed costs, and poor genetic merits of the local breeds of the country. This problem can be lessened by selecting best breed and modern animal breeding facilities, which require technologies like big data analysis and machine learning. In this study, a prediction model that can predict age at first calving of weaned calves based on their pre-weaning and weaning parameters, including dam’s parity number, season of calving, birth weight, pre-weaning health status, pre-weaning average daily weight gain (ADG), weaning age and weaning weight is developed. Primary data collected by Ardayta Dairy Research Centre; Ethiopia is used for this research. First, different pre-trained models developed using support vector regression (SVR), Linear support vector regression (LSVR) and Nu support vector regression (NuSVR) techniques with their default hyperparameter values in which SVR performed best. Second, a model was developed by tuning hyperparameters of SVR including kernel function, regularization (C-parameter) and gamma parameters, and it resulted in an accuracy of 96.46%. Next, Whale optimization technique is used to select the optimized features of the dataset. Furthermore, an ensemble of SVR, LSVR, NuSVR is designed, and the framework is trained by optimized features of data. The designed model achieved an accuracy of 98.3% superseding the other combinations.

Examining spatial equity in emergency facilities during the later stage of COVID-19 in China: insights from nucleic acid testing sites

Community-level emergency facilities are essential for disaster prevention and response, contributing significantly to urban health equity. This study aims to explore the multi-scale spatial pattern, multi-dimensional availability evaluation, and multi-scenario simulation optimization of nucleic acid testing sites during the later stage of COVID-19. At a macro scale, these sites demonstrated a "multi-core clustering" pattern, while at a micro-scale, they were community-centered, often located in areas with low traffic and better ventilation. Spatial accessibility analysis showed high accessibility in urban centers when only facility capacity was considered, though accessibility dropped relative to suburban areas when community population and time costs were included. Temporally, site availability followed an M-shaped distribution. This study optimized testing site locations, providing insights into equitable distribution and supply–demand balance for emergency facilities.

Концептуальные подходы, методические и экономические инструменты оценки функционирования и развития рынка услуг городского туризма

In the modern world, tourism, as an industry of interconnected sectors, influences the development of specific sectors of the economy and performs social and cultural functions. The article presents the author’s position, based on summaries of existing approaches and considering the paradigms of urbanization theory, that urban spaces today serve as a unifying sphere for various types of tourism, which are viewed as structural components of urban tourism. Based on the research fi ndings, the author provides a unique interpretation of the concepts ‘urban tourism’ and ‘urban tourism services market’, characterizing the urban tourism services market of Novosibirsk by highlighting various types of tourism resources – cultural-historical, architectural, infrastructural, etc.; the necessity for theoretical exploration of specific aspects of the urban tourism services market is argued. In particular, the possibility and necessity of implementing a conceptual economic model for assessing the current state and forecasting the development of the urban tourism services market based on the identification of basic factors of its functioning – demand potential and supply potential – are justified. The role of investment policy in the development of the urban tourism services market and the possibility of using cluster tools to activate demand and stimulate the sale of urban tourism services in the metropolis are outlined.

Employment of persons with disabilities: opportunities, priorities and outcomes of active policies in welfare states. Part one

This two-part article examines the active employment policies of welfare states and their impact on the situation of persons with disabilities of working age. On the basis of research materials and data from population surveys in the EU and OECD countries, the article analyzes the trends of active employment policies for persons with moderate and severe disabilities in welfare states of different models for the period from 2010 to 2020. The first part of the article reveals the approaches of active policy to retention on the labor market, to provision of employment assistance services, to reduction of unemployment risks, to employment of persons with disabilities. The principles of transformation of allowances for disability, temporary disability, unemployment, income maintenance and application of personal measures – incentives and sanctions, which are based on increasing the responsibility of citizens for their own well-being, are considered. The role of the factor of de-regulation of the employment sphere in the approaches of active policy to the expansion of labor supply and maintenance of demand on the part of employers is shown. The priorities of active measures to promote employment, based on cost reduction and increasing returns on investment, and their impact on the employment of citizens with different degrees of impairment are revealed. The results of active policies (employment gap and unemployment rate) and their sustainability in relation to persons with moderate and severe impairments are revealed.

Ecological Management Zoning Based on the Supply–Demand Relationship and Synergies of Urban Forest Ecosystem Services: A Case Study from Fuzhou, China

Urban forests, as vital components of green infrastructure, provide essential ecosystem services (ESs) that support urban sustainability. However, rapid urban expansion and increased density threaten these forests, creating significant imbalances between the supply and demand for these services. Understanding the characteristics of ecosystem services and reasonably dividing ecological management zones are crucial for promoting sustainable urban development. This study introduces an innovative ecological management zoning framework based on the matching degree and synergies relationships of ESs. Focusing on Fuzhou’s fourth ring road area in China, data from 1038 urban forest sample plots were collected using mobile LIDAR. By integrating the i-Tree Eco model and Kriging interpolation, we assessed the spatial distribution of four key ESs—carbon sequestration, avoided runoff, air purification, and heat mitigation—and analyzed their supply–demand relationships and synergies. Based on these ecological characteristics, we employed unsupervised machine learning classification to identify eight distinct ecological management zones, each accompanied by targeted recommendations. Key findings include the following: (1) ecosystem services of urban forests in Fuzhou exhibit pronounced spatial heterogeneity, with clearly identifiable high-value and low-value areas of significant statistical relevance; (2) heat mitigation, avoided runoff, and air purification services all exhibit synergistic effects, while carbon sequestration shows trade-offs with the other three services in high-value areas, necessitating targeted optimization; (3) eight ecological management zones were identified, each with unique ecological characteristics. This study offers precise spatial insights into Fuzhou’s urban forests, providing a foundation for sustainable ecological management strategies.

A Two-Stage Distributionally Robust Optimization Model for Managing Electricity Consumption of Energy-Intensive Enterprises Considering Multiple Uncertainties

Energy-intensive enterprises (EIEs), as vital demand-side flexibility resources, can significantly enhance the power system’s ability to regulate demand by participating in demand response (DR). This helps alleviate supply pressures during tight demand–supply conditions, ensuring the system’s safe and stable operation. However, due to the current level of electricity management in EIEs, their participation in demand response has disrupted the continuity of production to some extent, which may hinder the sustainability of demand-side management mechanisms. To address this issue, this paper proposes a two-stage distributionally robust optimization (DRO) model for managing production electricity in EIEs, considering multiple uncertainties. First, a production electricity load model based on the state task network (STN) is developed, reflecting the characteristics of industrial production lines. Next, a two-stage DRO model for day-ahead and intra-day electricity management is formulated, integrating an uncertainty set for distributed generation output based on the Wasserstein distance and probabilistic constraints for the day-ahead DR capacity. Finally, a cement plant in western China is used as a case study to validate the effectiveness of the proposed model. The results show that the proposed model effectively guides EIE in participating in DR while optimizing electricity costs, enabling cost savings of up to 27.7%.

The role of professional judgment in Indian real estate valuation: insights from lending industry experts

PurposeThe purpose of this study is to examine the role of professional judgment in property valuation within India’s lending sector by exploring how different market and cultural factors influence valuation practices.Design/methodology/approachA mixed-methods research approach comprising interviews of 15 highly experienced property valuation professionals to understand nuances of property valuation and find important factors which require their professional judgment, based on which a questionnaire survey is administered to 137 valuers from various parts of India. A relative importance index (RII) analysis and a mixed model ANOVA were then used to evaluate the significance of different factors affecting property valuation.FindingsThe results reveal the factors which require professional judgment of property valuation professionals. Zoning and development plans, legal due diligence, regulatory compliance, real estate regulatory authority and supply–demand dynamics are top five factors. Also, there was no statistically significant difference between less experienced property valuers and their more experienced counterparts.Practical implicationsThe findings reveal important factors which require professional judgment while doing valuation in opaque property markets of India. A study reveals difficulties that valuation teams working for banks and NBFCs face due to challenges and variation in Indian real estate markets. Furthermore, it stresses the need for continuous professional development and adherence to ethical standards among valuation professions.Originality/valueThis research offers an all-inclusive study about the things that influence subjective judgment in Indian property valuation and provides insight into the intricate intertwining of regulatory, market and cultural aspects in the process.